Containers, such as water bottles and food containers are currently made from many different types of materials, including plastics and glass. For example, food packaging and healthcare containers are often formed of glass in order to provide transparency, adequate oxygen and/or water barrier properties, and/or to address sterilization or hot filling processes. Glass containers, however, can fracture or break during production or transportation, which means production lines can be interrupted or stopped and/or goods can be rejected. Currently, glass that is used for packaging can withstand high heat sterilization conditions, hot filling, and remain transparent and/or possesses the capability for a long shelf-life. However the high energy costs involved with glass container production, the heavy weight of glass, and its fragility with production, transport, and consumer use are cumbersome.
While polymers such as PET (polyethylene terephthalate), PBT (polybutylene terephthalate), PEF (polyethylene furanoate), and PEN (polyethylene naphthalate) can possess better barrier properties for plastic bottles under select conditions(e.g., to water, oxygen (O2) and/or carbon dioxide (CO2) permeation) compared to polycarbonates, such materials can become hazy following heat treatment above the glass temperature of such materials. This haze formation can be due to inherent polymer properties (e.g., glass transition temperature (Tg) and crystallization half time) of these types of materials.
There accordingly is a need in the art for polycarbonate articles (e.g., bottles and food containers) that include improved functional barrier layers to prevent gas permeation and the migration of certain substances (for example, O2, CO2, and other components) between the articles (e.g., packaging) and the contents in the articles, while continuing to provide the beneficial attributes of polycarbonate materials such as one or more of transparency, strength, and thermal stability desired for many applications.